1. Field of Invention
The invention relates to cleaning media for cleaning recording mediums, more specifically to cleaning disks for cleaning transducers in flexible computer disk systems and packaging thereof.
2. Prior Art
In order to maintain the performance of flexible computer disk systems, it is necessary to clean the magnetic heads located within these systems. The magnetic heads are also referred to as transducers and will be referred to by either name throughout this specification. Since the transducers are difficult to access, various efforts have been made to devise disks which are commonly contained in flexible disk jackets to execute the required cleaning function.
Various prior art systems have been developed in an attempt to provide a convenient means of cleaning the transducer(s) on flexible disk systems. Typical prior art systems have utilized two flexible cleaning disks contained in jackets. One of the jackets contains an abrasive lapping material, and the other contains a cleaning cloth material. The first jacket is inserted into a flexible computer disk drive and run for a predetermined amount of time, generally no longer than 10 seconds. The time is specifically of short duration so the abrasive material will not cause damage to the magnetic heads. Damage usually occurs when the abrasive material in the disk loosens debris from the heads or the cleaning disk is run for too long a period of time. The second jacket is then inserted into the drive system and run so as to pick up the loosened debris. A disadvantage with this prior art is in the damage that may be caused by operating the cleaning disk for too long a period of time.
In IBM Technical Disclosure Bulletin, Volume 20, No. 8 January, 1978, there is described a standard flexible disk jacket having an abrasive disk therein instead of the normal magnetic disk. The abrasive disk is coated with either chromic oxide or aluminum oxide. The assembly is used to initially lap the magnetic heads of flexible disk drives and subsequently remove contaminant build up on the heads. A disadvantage with this type of disk is that it may leave particles of its own residue thus causing damage to the transducers.
In U.S. Pat. No. 4,180,840 to Allan there is described a cleaning disk that is only capable of cleaning one head of a two sided flexible disk drive at a time, a distinct disadvantage.
In U.S. Pat. Nos. 4,377,831; 4,374,404, and 4,498,114 all to Davis there is disclosed, a light colored fibrous non abrasive disk saturated with a cleaning solution which requires a specially designed jacket to accommodate the solution. Light colored disks of the type disclosed present a disadvantage because they are insufficiently opaque to activate the optical systems within the computer drive system, thus being incapable of loading the transducers onto the disk.
In U.S. Pat. No. 4,499,516 there is disclosed an opaque ring printed onto a disk to assure that the optical mechanism sensing the presence of the disk is activated and the transducers are loaded onto the disk.
In U.S. Pat. No. 4,065,798 to Sugisaki et al there is described a laminated disk which has a flexible nonmagnetic support (e.g. polyvinyl chloride) coated with a magnetic layer on one side and a fibrous cleaning material on the other side The cleaning disk is located within a cartridge which contains a lubricating layer facing the magnetic layer of the cleaning disk and includes a normal radial slit which allows the magnetic head to contact the fibrous cleaning material.
The latter two prior art cleaning disks have certain disadvantages. The use of a cleaning solution is messy and adds expense to the use of disks because they cannot be used without the solution In addition, there may be a hazard of flammability and/or toxicity associated with the solution. Commonly used cleaning solutions have been shown to extract components of vinyl jackets and to deposit said components via evaporation on the disk and/or the head. Such viscous mobile materials serve as an attractant for debris and can actually injure transducer performance. Furthermore, the cleaning solution may dissolve components of a printed black index track leading to a yellow discoloration of the disk. The use of the opaque ring adds expense to the manufacturing operation since it must be placed in a concentric orientation to the center hole.
Accordingly, it is an object of the present invention to provide a means of effectively cleaning both transducers of a two sided disk drive simultaneously without the use of cleaning solutions or of materials sufficiently abrasive to cause wear to the heads.
It is a further object of the invention to provide a completely white disk having sufficient opacity to activate the optical system located within the computer disk drive so as to facilitate the loading of the transducers onto the cleaning disk.
It is a further object of the invention to obviate the need for an opaque ring attached to or printed on the index track of the cleaning disk.
It is a further object of this invention to provide a transparent, clear jacket which permits visualization of removed and entrapped particles on the surface of the cleaning disk.